Programming Windows: Anders (Premium)

Anders Hejlsberg has been doing the impossible since his first foray into programming language and compiler design in 1980. An engineering prodigy, Anders was born in and grew up in Denmark, and he was lucky enough to attend one of the first high schools in the country to offer its students access to a computer, an HP 2100. After learning the ALGOL programming language on that computer, he enrolled in an engineering academy, and he started a software company with a schoolmate.

His first work with microcomputers came at age 20 with the Nascom kit computer, which was based on the Zilog Z80 microprocessor and came with Microsoft BASIC in ROM.

“I got curious about extending the Microsoft ROM BASIC, [which] had to fit into an 8K ROM,” Anders told Microsoft CTO Kevin Scott on the inaugural episode of the Behind the Tech podcast. “So there were a bunch of commands it didn't have. There was no renumber command, which was a royal pain in the neck, because if you ran out [line numbers] now, you had to manually go retype every line.  But there were some extension points where you could actually sort of hook into the ROM BASIC and because they were an extra slot for EPROMs on the motherboard. I wrote this little 4K ROM BASIC extension that gave you renumbering and a bunch of other things. It was like a little plug-in tool kit.”

Flush with that success, Anders considered bringing ALGOL to the Z80 or other early microprocessors, but a friend suggested that he check out the Pascal language, which had been designed by Niklaus Wirth about a decade earlier. What Anders created was “a little Pascal that was effectively the nascent Turbo Pascal,” complete with an onscreen editor, a runtime library, and a compiler. “And it was all squeezed into 12K in a ROM,” he said, noting that it was written in Z80 Assembler and ran on CP/M.

The significance of this achievement cannot be overstated. Not only had Anders squeezed all of that functionality into a tiny space---other Pascal implementations were much bigger, less full-featured, and required a monotonous number of disk swaps before anything would happen---but he had also created one of the first-ever integrated development environments (IDEs).

Anders evolved his little Pascal until it became a full implementation of the language, and he finally met the founders of Borland, another Denmark-based firm that was using something called Pascal MT+, which was sold by CP/M maker Digital Research. “That was a horrible Pascal,” Anders recalled, and so he showed them the product he had created. Borland immediately hired Anders, and licensed his compiler and other tools, and sold it as Turbo Pascal, dropping the price from the $500 Anders had been charging to just $49.95. The result was a blockbuster smash hit, and Borland “literally sold four or five orders of magnitude more copies.”

As the lead architect for Turbo Pascal and then later Delphi, an object-oriented RAD evolution of Tu...